SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Related Amortization Expense of Purchase Accounting Intangible Assets (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Aggregate amortization expense for the year ended December 31:
2018	$ 1,656
2019	3,216
2020	4,093
Estimated amortization expense for the year ending December 31:
2021	4,137
2022	3,967
2023	3,921
2024	3,891
2025	3,876
Thereafter	10,964
Net Carrying Amount, Core deposits	$ 30,756

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Amount of amortization expense expected to be recognized in the remainder of the fiscal year one following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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Amount of amortization expense expected to be recognized in the remainder of the fiscal year three following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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Amount of amortization expense expected to be recognized in the remainder of the fiscal year two following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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No definition available.

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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